Abstract: A laser apparatus includes: a laser oscillator that includes a mirror and emits a laser beam; and an external resonator that includes a nonlinear optical crystal that functions as a phase conjugate mirror. The phase conjugate mirror reflects the laser beam and produces a phase conjugate wave that reaches the mirror of the laser oscillator, and the mirror of the laser oscillator and the phase conjugate mirror cause laser oscillation such that a wavelength and a phase of the laser beam oscillated by the laser oscillation are automatically fixed.

Abstract: A fiber laser apparatus includes: a short-length type fiber to which an active element is added and that has a length of 300 mm or less: a ferrule attached to an end of the fiber; and a housing that accommodates the fiber and supports the fiber with the ferrule. Each of the housing and the ferrule is composed of a material having a first thermal expansion coefficient that is equal to or have a predetermined difference from a second thermal expansion coefficient of a raw material of the fiber. The predetermined difference between the first and second thermal expansion coefficients is within ?8.6×10?6 to 11.4×10?6/K.

Abstract: An ultraviolet laser apparatus includes: a semiconductor laser that emits an excitation laser light; a fiber laser medium to which the excitation laser light enters from the semiconductor laser and that causes laser oscillation; and an external resonator that: converts a wavelength of a laser light oscillated in the fiber laser medium, and outputs an ultraviolet region continuous wave of at least 0.1W.

Abstract: A fiber laser apparatus includes: a short-length type fiber to which an active element is added and that has a length of 300 mm or less: a ferrule attached to an end of the fiber; and a housing that accommodates the fiber and supports the fiber with the ferrule. Each of the housing and the ferrule is composed of a material having a first thermal expansion coefficient that is equal to or have a predetermined difference from a second thermal expansion coefficient of a raw material of the fiber. The predetermined difference between the first and second thermal expansion coefficients is within ?8.6×10?6 to 11.4×10?6/K.

Abstract: A laser apparatus includes: a laser oscillator that includes a mirror and emits a laser beam; and an external resonator that includes a nonlinear optical crystal that functions as a phase conjugate mirror. The phase conjugate mirror reflects the laser beam and produces a phase conjugate wave that reaches the mirror of the laser oscillator, and the mirror of the laser oscillator and the phase conjugate mirror cause laser oscillation such that a wavelength and a phase of the laser beam oscillated by the laser oscillation are automatically fixed.

Abstract: A system for reducing pathogen proliferation on a device includes a waveguide disposed on a body of the device and including a first layer of transparent material having a first refractive index greater than a second refractive index of the body of the device and a third refractive index of an environment in contact with an outer surface of the first layer. A first light source is configured to emit light having a first range of wavelengths into the first layer. The light is substantially confined within the waveguide by total internal reflection. Total internal reflection is frustrated at points of contact between the pathogens or a medium in which the pathogens are suspended and an outer surface of the waveguide, thereby scattering a portion of the light out of the waveguide and into the pathogens and, thereby, reducing proliferation of the pathogens. Related methods are also provided.

Abstract: A device configured to cut hair using laser light includes a handle portion and a shaving portion. The handle portion includes a battery and a laser light source. The laser light source is coupled to and configured to receive power from the battery. The laser light source is also configured to generate laser light having a wavelength selected to target a predetermined chromophore to effectively cut a hair shaft. The shaving portion includes a support and a single fiber optic supported by the support. The fiber optic has a proximal end, a distal end, an outer wall, and a cutting region positioned towards the distal end and extending along a portion of the side wall. The fiber optic is positioned to receive the laser light from the laser light source at the proximal end, conduct the laser light from the proximal end toward the distal end, and emit the light out of the cutting region and toward hair when the cutting region is brought in contact with the hair.

Abstract: A device configured to cut hair using laser light includes a handle portion and a shaving portion. The handle portion includes a battery and a laser light source. The laser light source is coupled to and configured to receive power from the battery. The laser light source is also configured to generate laser light having a wavelength selected to target a predetermined chromophore to effectively cut a hair shaft. The shaving portion includes a support and a single fiber optic supported by the support. The fiber optic has a proximal end, a distal end, an outer wall, and a cutting region positioned towards the distal end and extending along a portion of the side wall. The fiber optic is positioned to receive the laser light from the laser light source at the proximal end, conduct the laser light from the proximal end toward the distal end, and emit the light out of the cutting region and toward hair when the cutting region is brought in contact with the hair.

Abstract: A device configured to cut hair using laser light includes a handle portion and a shaving portion. The handle portion includes a battery and a laser light source. The laser light source is coupled to and configured to receive power from the battery. The laser light source is also configured to generate laser light having a wavelength selected to target a predetermined chromophore to effectively cut a hair shaft. The shaving portion includes a support and a single fiber optic supported by the support. The fiber optic has a proximal end, a distal end, an outer wall, and a cutting region positioned towards the distal end and extending along a portion of the side wall. The fiber optic is positioned to receive the laser light from the laser light source at the proximal end, conduct the laser light from the proximal end toward the distal end, and emit the light out of the cutting region and toward hair when the cutting region is brought in contact with the hair.

Abstract: A device configured to cut hair using laser light includes a handle portion and a shaving portion. The handle portion includes a battery and a laser light source. The laser light source is coupled to and configured to receive power from the battery. The laser light source is also configured to generate laser light having a wavelength selected to target a predetermined chromophore to effectively cut a hair shaft. The shaving portion includes a support and a single fiber optic supported by the support. The fiber optic has a proximal end, a distal end, an outer wall, and a cutting region positioned towards the distal end and extending along a portion of the side wall. The fiber optic is positioned to receive the laser light from the laser light source at the proximal end, conduct the laser light from the proximal end toward the distal end, and emit the light out of the cutting region and toward hair when the cutting region is brought in contact with the hair.

Abstract: A device configured to cut hair using laser light includes a handle portion and a shaving portion. The handle portion includes a battery and a laser light source. The laser light source is coupled to and configured to receive power from the battery. The laser light source is also configured to generate laser light having a wavelength selected to target a predetermined chromophore to effectively cut a hair shaft. The shaving portion includes a support and a single fiber optic supported by the support. The fiber optic has a proximal end, a distal end, an outer wall, and a cutting region positioned towards the distal end and extending along a portion of the side wall. The fiber optic is positioned to receive the laser light from the laser light source at the proximal end, conduct the laser light from the proximal end toward the distal end, and emit the light out of the cutting region and toward hair when the cutting region is brought in contact with the hair.

Abstract: A device configured to cut hair using laser light includes a handle portion and a shaving portion. The handle portion includes a battery and a laser light source. The laser light source is coupled to and configured to receive power from the battery. The laser light source is also configured to generate laser light having a wavelength selected to target a predetermined chromophore to effectively cut a hair shaft. The shaving portion includes a support and a single fiber optic supported by the support. The fiber optic has a proximal end, a distal end, an outer wall, and a cutting region positioned towards the distal end and extending along a portion of the side wall. The fiber optic is positioned to receive the laser light from the laser light source at the proximal end, conduct the laser light from the proximal end toward the distal end, and emit the light out of the cutting region and toward hair when the cutting region is brought in contact with the hair.

Abstract: A device configured to cut hair using laser light includes a handle portion and a shaving portion. The handle portion includes a battery and a laser light source. The laser light source is coupled to and configured to receive power from the battery. The laser light source is also configured to generate laser light having a wavelength selected to target a predetermined chromophore to effectively cut a hair shaft. The shaving portion includes a support and a single fiber optic supported by the support. The fiber optic has a proximal end, a distal end, an outer wall, and a cutting region positioned towards the distal end and extending along a portion of the side wall. The fiber optic is positioned to receive the laser light from the laser light source at the proximal end, conduct the laser light from the proximal end toward the distal end, and emit the light out of the cutting region and toward hair when the cutting region is brought in contact with the hair.

Abstract: A device configured to cut hair using laser light includes a handle portion and a shaving portion. The handle portion includes a battery and a laser light source. The laser light source is coupled to and configured to receive power from the battery. The laser light source is also configured to generate laser light having a wavelength selected to target a predetermined chromophore to effectively cut a hair shaft. The shaving portion includes a support and a single fiber optic supported by the support. The fiber optic has a proximal end, a distal end, an outer wall, and a cutting region positioned towards the distal end and extending along a portion of the side wall. The fiber optic is positioned to receive the laser light from the laser light source at the proximal end, conduct the laser light from the proximal end toward the distal end, and emit the light out of the cutting region and toward hair when the cutting region is brought in contact with the hair.

Abstract: Systems and methods for use with an optical communication beam are disclosed. The system allows the beam of light to operate at an adequate power level that provides a robust optical link while minimizing any safety risk to humans. The system calibrates and controls the gain for an avalanche photodiode detector (APD). A detector circuit is used to calibrate the APD. Once calibrated, the detector circuit further provides an electrical bias to the APD to process or condition the electrical signal to produce a detector output. The systems and methods disclosed herein attenuate the power level of an incoming communication beam to prevent oversaturation of an APD. The system further provides an alignment signal, which is effective over a wide dynamic range of incoming power levels.